1. Field of the Invention
The present invention relates to an error information acquiring method, an error information acquiring program product, an error information acquiring device, a print controlling method, a print controlling program product and a print controlling device for acquiring information for compensating color drifts in any printing devices for printing images corresponding to printing data by means of printing heads.
2. Description of the Prior Art
Each of the ink jet printers that have been mass-produced in the past has an array of printing nozzles for each color (type) of ink and a nonvolatile semiconductor memory containing an ID (error information) for compensating drifts in the weight of ink discharged from each array of printing nozzles. For controlling the printing of each printer, color correcting data such as a LUT (look up table) for calibration corresponding to the ID are prepared in advance and are stored, and errors in the weight of ink are compensated so that the weight of ink discharged from the printing head may agree with that of the reference printer (reference equipment) by referring the color correcting data corresponding to the ID. (For example, see Japanese Patent Application Laid Open 1998-278360).
And the applicant has already filed an application (Japanese Patent Application 2004-35947) relating to the invention of a print controlling device for correcting variations in color reproducibility that appear between various printers and the reference equipment by using the ID indicating the result of comparison between the measured color data of patch images printed by a printer due to be mass-produced based on the specified printing data and the reference measured color data.
In addition, the applicant has already filed an application (Japanese Patent Application 2004-20989) relating to the invention of a print controlling device for correcting variations in color reproducibility that appear in various printer by having the patch images printed by the printer due to be mass-produced each printing head being filled with a different alternative ink from the ink that should be normally used therein, by acquiring an ID indicating the result of comparison between the converted value of the measured color data of the patch images and the reference measured color data and by using the acquired ID.
Although each of the prior applications mentioned above is useful for setting the ID for each printer for example when the printer is mass-produced, there is no assurance that the ID setting will continue to be used in each printer. And it will be necessary to reset the ID, for example, when the printing head or various components constituting the printing head is or are replaced. Here, the ID that had already been set was chosen by comparing the result of measuring the colors of the patch images printed under the specified conditions among various printing conditions that vary depending on the type of ink or the type of printing medium used and the specified reference data. Therefore, even in the case of acquiring the ID again, it is necessary to print the patch images essentially under the same printing conditions as the ones under which the ID had been set in the past and to measure their color.
However, in the case of resetting the ID, it is in reality difficult in view of differences in facilities and the acquisition of materials and cost to obtain always the same printing conditions for printing patch images as in the previous case of setting the ID for the mass production of printers. Therefore, even when it has become necessary to reset the ID, sometimes it was not possible to acquire the correct ID for compensating variations in color reproducibility that appears in various printers.
And when the ID is to be reset again, it is difficult for certain types of ink to adhere on the printing medium depending on the combination of the printing medium and the ink made available for printing the patch images and as a result patch images sometimes cannot be printed. In such a case, it will be more difficult to obtain a correct ID.